Method of catalytic conversion of butane

Abstract

In a method of catalytic conversion of a butane cut to propane, a butane cut and hydrogen are introduced respectively into a reaction zone containing a catalyst consisting of mordenite in acid form in such a manner as to ensure that the partial pressure of hydrogen is higher than 5 bar.

What we claim is: 
     
       1. A method of catalytic conversion of a butane cut to propane, wherein said method consists in introducing into a reaction zone containing a catalyst consisting of acid mordenite on the one hand a butane cut and on the other hand hydrogen so that the partial hydrogen pressure is higher than 5 bar. 
     
     
       2. A method according to claim 1, wherein the mordenite is in its hydrogen form. 
     
     
       3. A method according to claim 1, wherein the exchangeable cations of the mordenite are selected from the alkaline earths and/or the rare earths. 
     
     
       4. A method according to claim 1, wherein the mordenite employed has a silicon/aluminum ratio which is higher than 10. 
     
     
       5. A method according to claim 4, wherein the mordenite employed has been obtained by de-alumination of a conventional mordenite by means of acid solvents. 
     
     
       6. A method according to claim 1, wherein the temperature of operation is within the range of 250° to 550° C. 
     
     
       7. A method according to claim 1, wherein the partial hydrogen pressure is within the range of 20 to 80 bar. 
     
     
       8. A method according to claim 1, wherein the hydrogen/butane molar ratio is within the range of 2 to 20. 
     
     
       9. A method according to claim 1, wherein the spatial rate of introduction of the feedstock in liquid form is within the range of 0.1 to 10 h -1 . 
     
     
       10. A method according to claim 1, wherein the partial hydrogen pressure is within the range of 5 to 100 bar. 
     
     
       11. A method according to claim 6, wherein the temperature of operation is within the range of 325° to 450° C. 
     
     
       12. A method according to claim 7, wherein the partial hydrogen pressure is within the range of 20 to 40 bar. 
     
     
       13. A method according to claim 8 wherein the hydrogen/butane molar ratio is within the range of 2 to 8. 
     
     
       14. A method according to claim 9 wherein the spatial rate of introduction of the feedstock in liquid form is within the range of 0.5 to 5 h -1 . 
     
     
       15. A method of catalytically converting n and iso-butanes into propane comprising introducing the butane cut feedstock in liquid form at a spatial rate within the range of 0.1 to 10 h -1  into a reaction zone containing as catalyst an acid mordenite and having a partial hydrogen pressure of between 5 and 100 bar, the hydrogen/butane molar ratio is in the range of 2 to 20, said conversion conducted at a temperature within the range of 250° to 550° C, thereby catalytically converting said butane cut to propane. 
     
     
       16. In a catalytic process for converting a butane cut into propane, the improvement comprising contacting said butane cut with an acid mordenite catalyst in the presence of a partial hydrogen pressure of 20 to 80 bar in a reaction zone at a temperature of about 325° to 450° C, said process characterized by: a hydrogen/butane molar ratio within the range of 2 to 8, and   a spatial rate of liquid butane feedstock introduction with the range of 0.5 to 5 h -1 , thereby resulting in improved propane yields and avoiding the use of a hydrogenating metal.